The present invention relates to a control pulse generator for initializing an internal circuit of a semiconductor integrated circuit (IC).
A control pulse generator, used for initialization, supplies an initializing pulse having a predetermined width to an IC internal circuit, such as a flip-flop, to be initialized upon energization (or power-on) of the IC circuit.
In an arrangement of a conventional control pulse generator, the width and height of an initializing pulse vary in accordance with the rise time of a power supply voltage upon energization of the control pulse generator. Therefore, when the rise time of the power supply voltage varies, the width and height of the initializing pulse vary considerably, thus posing a problem.
In general, the rise time of a power supply voltage of a semiconductor integrated circuit depends on a peripheral system coupled to the integrated circuit. Variations in the rise time of the power supply voltage, due to use of various peripheral systems, range from several nsec to several msec. Therefore, if the conventional control pulse generator is normally used, a control pulse having a sufficient width and height (voltage value) for initialization could not be supplied to an IC internal circuit, except for a specific system having a predetermined rise time of a power supply voltage well-matched to the conventional control pulse generator.